diff --git a/zipserver/music_analyzer.go b/zipserver/music_analyzer.go
index 0f5d461..3c182ce 100644
--- a/zipserver/music_analyzer.go
+++ b/zipserver/music_analyzer.go
@@ -6,7 +6,6 @@ import (
 	"io"
 
 	"github.com/dhowden/tag"
-	"github.com/go-errors/errors"
 )
 
 // MusicAnalyzer uses rules according to music albums.
@@ -15,7 +14,7 @@ import (
 type MusicAnalyzer struct{}
 
 func (m MusicAnalyzer) Analyze(r io.Reader, key string) (AnalyzeResult, error) {
-	res := AnalyzeResult{Key: key}
+	res := AnalyzeResult{}
 
 	// TODO: The music tag library requires a ReadSeeker (understandably),
 	// which a Reader does not satisfy. Here is a naive implementation that
@@ -25,13 +24,17 @@ func (m MusicAnalyzer) Analyze(r io.Reader, key string) (AnalyzeResult, error) {
 
 	b, err := io.ReadAll(r)
 	if err != nil {
-		return res, errors.Wrap(err, 0)
+		return res, fmt.Errorf("read bytes: %w", err)
 	}
 
 	rs := bytes.NewReader(b)
 	md, err := tag.ReadFrom(rs)
 	if err != nil {
-		return res, errors.Wrap(err, 0)
+		// Tag parser expects at least 11 bytes.
+		if err == io.ErrUnexpectedEOF {
+			return res, fmt.Errorf("%w: file too short", ErrSkipped)
+		}
+		return res, fmt.Errorf("new tag reader: %w", err)
 	}
 
 	// Package tag provides these already, but let's set them explicitly
@@ -71,6 +74,7 @@ func (m MusicAnalyzer) Analyze(r io.Reader, key string) (AnalyzeResult, error) {
 		Lyrics:      md.Lyrics(),
 		Comment:     md.Comment(),
 	}
+	res.Key = key
 
 	return res, nil
 }
diff --git a/zipserver/music_analyzer_test.go b/zipserver/music_analyzer_test.go
new file mode 100644
index 0000000..81c880d
--- /dev/null
+++ b/zipserver/music_analyzer_test.go
@@ -0,0 +1,97 @@
+package zipserver
+
+import (
+	"bytes"
+	"embed"
+	"errors"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+//go:embed testdata/music/*
+var testAudioFiles embed.FS
+
+func TestMusicAnalyzer(t *testing.T) {
+	testCases := []struct {
+		name string
+		err  error
+		res  AnalyzeResult
+	}{
+		{
+			name: "tone.thisisflac",
+			res: AnalyzeResult{
+				Key:         "key",
+				ContentType: "audio/flac",
+				Metadata: TrackInfo{
+					FileType:    "FLAC",
+					Title:       "Long drone",
+					Album:       "Fall asleep",
+					Artist:      "Smith",
+					AlbumArtist: "Smith",
+					Composer:    "Smith",
+					Year:        2005,
+					Track:       4,
+					TrackTotal:  6,
+					Disc:        2,
+					DiscTotal:   2,
+				},
+			},
+		},
+		{
+			name: "tone.thisisopus",
+			res: AnalyzeResult{
+				Key:         "key",
+				ContentType: "audio/ogg",
+				Metadata: TrackInfo{
+					FileType:   "Ogg",
+					Title:      "Halloween song 2",
+					Album:      "Don't listen to any of these songs",
+					Artist:     "Creepy Weirdo",
+					Genre:      "horror",
+					Year:       2022,
+					Track:      12,
+					TrackTotal: 666,
+					Lyrics:     "pumpkins yeah\\ndecorate your house",
+					Comment:    "spooky tune",
+				},
+			},
+		},
+		{
+			name: "tone.thisismp3",
+			res: AnalyzeResult{
+				Key:         "key",
+				ContentType: "audio/mpeg",
+				Metadata: TrackInfo{
+					FileType:   "MP3",
+					Title:      "Boring",
+					Album:      "Wat?",
+					Artist:     "Small Dude",
+					Genre:      "Acoustic",
+					Year:       1994,
+					Track:      2,
+					TrackTotal: 10,
+					Comment:    "wrote this when I was bored",
+				},
+			},
+		},
+		{
+			name: "garbage.dat",
+			err:  ErrSkipped,
+		},
+	}
+
+	var analyzer MusicAnalyzer
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			b, err := testAudioFiles.ReadFile("testdata/music/" + tc.name)
+			require.NoError(t, err)
+			buf := bytes.NewBuffer(b)
+			res, err := analyzer.Analyze(buf, "key")
+			require.Truef(t, errors.Is(err, tc.err), "error %q does not wrap %q", err, tc.err)
+			assert.Equal(t, tc.res, res)
+		})
+	}
+}
diff --git a/zipserver/testdata/music/README.txt b/zipserver/testdata/music/README.txt
new file mode 100644
index 0000000..91b0194
--- /dev/null
+++ b/zipserver/testdata/music/README.txt
@@ -0,0 +1 @@
+Data files are renamed to test content detection.
diff --git a/zipserver/testdata/music/garbage.dat b/zipserver/testdata/music/garbage.dat
new file mode 100644
index 0000000..02e5641
--- /dev/null
+++ b/zipserver/testdata/music/garbage.dat
@@ -0,0 +1 @@
+
þýDˆÌ`
\ No newline at end of file
diff --git a/zipserver/testdata/music/tone.thisisflac b/zipserver/testdata/music/tone.thisisflac
new file mode 100644
index 0000000..212aad6
Binary files /dev/null and b/zipserver/testdata/music/tone.thisisflac differ
diff --git a/zipserver/testdata/music/tone.thisismp3 b/zipserver/testdata/music/tone.thisismp3
new file mode 100644
index 0000000..8c83599
Binary files /dev/null and b/zipserver/testdata/music/tone.thisismp3 differ
diff --git a/zipserver/testdata/music/tone.thisisopus b/zipserver/testdata/music/tone.thisisopus
new file mode 100644
index 0000000..cbc729b
Binary files /dev/null and b/zipserver/testdata/music/tone.thisisopus differ